Analysis of The train dogs

Out of the night and the north;
 Savage of breed and of bone,
Shaggy and swift comes the yelping band,
Freighters of fur from the voiceless land
 That sleeps in the Arctic zone.

Laden with skins from the north,
 Beaver and bear and raccoon,
Marten and mink from the polar belts,
Otter and ermine and sable pelts--
 The spoils of the hunter's moon.

Out of the night and the north,
 Sinewy, fearless and fleet,
Urging the pack through the pathless snow,
The Indian driver, calling low,
 Follows with moccasined feet.

Ships of the night and the north,
 Freighters on prairies and plains,
Carrying cargoes from field and flood
They scent the trail through their wild red blood,
 The wolfish blood in their veins.